Sexual Reproduction
... Urethra-Tube within the penis that carries urine or sperm out of the body. Penis- structural adaptation for internal fertilization. Other structures associated with the male productive system produce the fluids and nutrients that are needed for the proper function and delivery of the male gametes ...
... Urethra-Tube within the penis that carries urine or sperm out of the body. Penis- structural adaptation for internal fertilization. Other structures associated with the male productive system produce the fluids and nutrients that are needed for the proper function and delivery of the male gametes ...
Human Reproduction
... in the image below. Once a male reaches puberty, the reproductive system will produce sperm almost continuously, until the end of his life. Females, however, are born with all of the potential eggs they will ever have—about 400,000. After puberty, one egg matures a month. This means that during a fe ...
... in the image below. Once a male reaches puberty, the reproductive system will produce sperm almost continuously, until the end of his life. Females, however, are born with all of the potential eggs they will ever have—about 400,000. After puberty, one egg matures a month. This means that during a fe ...
Patterns of sexual dimorphism in Mexican alligator lizards, Barisia
... (Zaldivar-River on et al. 2005). One of the only mechanisms to explain hypothesis 2 would be if female color pattern in B. imbricata is under sexual selection, but the same trait in males is not subject to selection. Although male mate choice is not common in lizards, it has been observed in Scelop ...
... (Zaldivar-River on et al. 2005). One of the only mechanisms to explain hypothesis 2 would be if female color pattern in B. imbricata is under sexual selection, but the same trait in males is not subject to selection. Although male mate choice is not common in lizards, it has been observed in Scelop ...
Haplochromis burtoni – Burton`s Mouthbrooder
... that may influence perception - to enhance female visual acuity and ability to differentiate between dominant males (Martin 2004). Male courtship display consists of the male quivering in front of the female with the anal fin spread, then leading her toward the pit for spawning. The female releases ...
... that may influence perception - to enhance female visual acuity and ability to differentiate between dominant males (Martin 2004). Male courtship display consists of the male quivering in front of the female with the anal fin spread, then leading her toward the pit for spawning. The female releases ...
The origin of gender and sexual reproduction
... become pregnant, and that the great majority of male mammals normally don’t lactate. But one has to go further and ask why mammals evolved genes specifying that only females, not males, would develop the necessary anatomical equipment, the priming experience of pregnancy, and the necessary hormones. ...
... become pregnant, and that the great majority of male mammals normally don’t lactate. But one has to go further and ask why mammals evolved genes specifying that only females, not males, would develop the necessary anatomical equipment, the priming experience of pregnancy, and the necessary hormones. ...
Adaptation and Evolution – How do species change over time?
... parental investment leads to very different strategies for males and females (main thrust of Triver’s famous 1972 paper) Females – be very choosy – choose males that will provide assistance, good territory, good genes etc. Males – go for as many fertilizations as possible and move on – little or not ...
... parental investment leads to very different strategies for males and females (main thrust of Triver’s famous 1972 paper) Females – be very choosy – choose males that will provide assistance, good territory, good genes etc. Males – go for as many fertilizations as possible and move on – little or not ...
Sexual reproduction in Human beings
... Identify on diagrams of the male reproductive system and give the functions of testes, scrotum, sperm ducts, prostate gland, urethra and penis Identify on diagrams of the female reproductive system and give the functions of ovaries, oviducts, uterus, cervix and vagina Compare male and female gametes ...
... Identify on diagrams of the male reproductive system and give the functions of testes, scrotum, sperm ducts, prostate gland, urethra and penis Identify on diagrams of the female reproductive system and give the functions of ovaries, oviducts, uterus, cervix and vagina Compare male and female gametes ...
Model Details - Virtual Biology Lab
... Darwin (1871) defined sexual selection as selection on those traits specifically involved with acquiring mates. Examples of traits that are thought to be sexually selected include bright, conspicuous coloration (e.g. a peacock’s tail) to attract mates, or weaponry in males (e.g. tusks or horns) to b ...
... Darwin (1871) defined sexual selection as selection on those traits specifically involved with acquiring mates. Examples of traits that are thought to be sexually selected include bright, conspicuous coloration (e.g. a peacock’s tail) to attract mates, or weaponry in males (e.g. tusks or horns) to b ...
Reproduction
... Desirable traits can be restored due to offspring are genetically identical to parents. ...
... Desirable traits can be restored due to offspring are genetically identical to parents. ...
Functions of Female Reproductive Organs
... • The placenta is an organ made of two tissues: mother’s uterine tissue and foetal tissue • The bloodstream of the foetus and mother DO NOT mix, but come into close contact so that materials can be ...
... • The placenta is an organ made of two tissues: mother’s uterine tissue and foetal tissue • The bloodstream of the foetus and mother DO NOT mix, but come into close contact so that materials can be ...
File
... Marine iguanas (Amblyrhynchus cristatus) are found on the Galapagos islands of Genovesa and Santa Fe. Marine iguanas are unique among lizards in that they feed on algae in the intertidal zone. Between feeding they lie in the sun to warm themselves. Male iguanas establish territories on the rocks whe ...
... Marine iguanas (Amblyrhynchus cristatus) are found on the Galapagos islands of Genovesa and Santa Fe. Marine iguanas are unique among lizards in that they feed on algae in the intertidal zone. Between feeding they lie in the sun to warm themselves. Male iguanas establish territories on the rocks whe ...
Butterflies~RF6c1e29.TMP
... pattern. When a male sights a potential mate it will fly closer, often behind or above the female. Once closer, the male will release special chemicals, called pheromones, while it flutters its wings a bit more than usual. The male may also do a special "courtship dance" to attract the female. These ...
... pattern. When a male sights a potential mate it will fly closer, often behind or above the female. Once closer, the male will release special chemicals, called pheromones, while it flutters its wings a bit more than usual. The male may also do a special "courtship dance" to attract the female. These ...
The Importance Of Female Choice - Chapman University Digital
... sexual motivations in the field of primatology, and even in popular culture. Hrdy (1977, 1981) provided some of the first challenges to the conclusions drawn from parental investment theory. Her accounts of sexual behavior among Hanuman langur monkeys revealed sexually ardent behavior by females, wh ...
... sexual motivations in the field of primatology, and even in popular culture. Hrdy (1977, 1981) provided some of the first challenges to the conclusions drawn from parental investment theory. Her accounts of sexual behavior among Hanuman langur monkeys revealed sexually ardent behavior by females, wh ...
Sexual Selection and Reproductive Behaviour
... And this leads me to say a few words on what I call Sexual Selection. This depends, not on a struggle for existence, but on a struggle between the males for possession of the females; the result is not death to the unsuccessful competitor, but few or no offspring. Sexual selection is, therefore, le ...
... And this leads me to say a few words on what I call Sexual Selection. This depends, not on a struggle for existence, but on a struggle between the males for possession of the females; the result is not death to the unsuccessful competitor, but few or no offspring. Sexual selection is, therefore, le ...
File
... move water over gills Move water over EGGS, transfer sperm (males) carry young/eggs (females) Propulsion during tailflips ...
... move water over gills Move water over EGGS, transfer sperm (males) carry young/eggs (females) Propulsion during tailflips ...
Black-and-white Ruffed Lemur: Size: Head and body 51
... Why the colourful face? Males usually make up only 7% of the population, suggesting fierce competition among the males for breeding positions. In this competition, males gain advantage in prominently advertising his social position and readiness to mate. This may also explain why males are more than ...
... Why the colourful face? Males usually make up only 7% of the population, suggesting fierce competition among the males for breeding positions. In this competition, males gain advantage in prominently advertising his social position and readiness to mate. This may also explain why males are more than ...
Nephila clavipes (Golden Orb Weaver)
... sometimes get trapped in the webs as seen in Fig. 4. They also have a venomous bite that they use in defence but the sting is not very severe and would not kill a larger sized predator e.g. humans who only show mild symptoms from a bite such as swelling and mild pain. Another way this spider protect ...
... sometimes get trapped in the webs as seen in Fig. 4. They also have a venomous bite that they use in defence but the sting is not very severe and would not kill a larger sized predator e.g. humans who only show mild symptoms from a bite such as swelling and mild pain. Another way this spider protect ...
Unit 2
... Mothers and Others, S. B. Hrdy, 2001 1. What new evidence suggests how prehuman moms managed to raise such huge and dependent children? 2. According to W.D. Hamilton, what does evolutionary logic predict that an animal with poor prospects of reproducing on his/her own should do? 3. What hormonal ch ...
... Mothers and Others, S. B. Hrdy, 2001 1. What new evidence suggests how prehuman moms managed to raise such huge and dependent children? 2. According to W.D. Hamilton, what does evolutionary logic predict that an animal with poor prospects of reproducing on his/her own should do? 3. What hormonal ch ...
File
... Evidently, the feathers have been demonstrated to be associated with courtship and mate selection, ability to attract female peacocks (called peahens) ...
... Evidently, the feathers have been demonstrated to be associated with courtship and mate selection, ability to attract female peacocks (called peahens) ...
Mating: Sexual selection
... − if they improve the males’ reproductive success by increasing matings − more than they harm reproductive success by increasing predation or other costs − two kinds of sexual selection: − intrasexual selection: selection that occurs due to differences in success at mating that result from interacti ...
... − if they improve the males’ reproductive success by increasing matings − more than they harm reproductive success by increasing predation or other costs − two kinds of sexual selection: − intrasexual selection: selection that occurs due to differences in success at mating that result from interacti ...
repo. bookwork Key
... The human oocyte becomes an ovum only if sperm penetration occurs, at which time the secondary oocyte completes the second meiotic division to produce the ovum nucleus and a polar body, which is ejected. #17. List and describe the events of the menstrual cycle. Why is the menstrual cycle important? ...
... The human oocyte becomes an ovum only if sperm penetration occurs, at which time the secondary oocyte completes the second meiotic division to produce the ovum nucleus and a polar body, which is ejected. #17. List and describe the events of the menstrual cycle. Why is the menstrual cycle important? ...
repo. bookwork Key
... The human oocyte becomes an ovum only if sperm penetration occurs, at which time the secondary oocyte completes the second meiotic division to produce the ovum nucleus and a polar body, which is ejected. #17. List and describe the events of the menstrual cycle. Why is the menstrual cycle important? ...
... The human oocyte becomes an ovum only if sperm penetration occurs, at which time the secondary oocyte completes the second meiotic division to produce the ovum nucleus and a polar body, which is ejected. #17. List and describe the events of the menstrual cycle. Why is the menstrual cycle important? ...
NS&SS
... male and 6 females (results same, so pooled) As predicted, female reproductive success increases more steeply with more mates than for males open, solid line=male filled, dashed line=female ...
... male and 6 females (results same, so pooled) As predicted, female reproductive success increases more steeply with more mates than for males open, solid line=male filled, dashed line=female ...
Female Reproductive System
... If pregnancy does not occur... • If fertilization does not occur, the egg does not implant in the uterus. It may pass out of the females body, or be absorbed by the females body. • If implantation does not occur, the females body begins the process of menstruation, where the body builds a new uteri ...
... If pregnancy does not occur... • If fertilization does not occur, the egg does not implant in the uterus. It may pass out of the females body, or be absorbed by the females body. • If implantation does not occur, the females body begins the process of menstruation, where the body builds a new uteri ...